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17

Once the cylinder is released and starts to accelerate downward, the rotating flyweights should pivot upwards to a certain degree (as shown in the drawing) and should act as a drag on each of the motors' rotor shafts and thus a drag on the falling cylinder No, there is no reason for them to pivot upwards. The gravity pulls the flyweights with the same ...


6

It approximately means it is allowed or forbidden to have scratches at the place of round. When you are making cylinder surface you can to do it many different ways: milling, welding, soldering. In one case must be strong requriment for smoothness of surface (for example in bearings need to minimize friction). In other cases it is allowed to have scratches (...


6

I think you might have a misconception regarding to how far the pressure from the fasteners extends. One subject you might want to have a look into is "bolt joint stiffness". The most popular is the "Rotscher’s pressure-cone method". Essentially there is a pressure cone which radiates outwards with an pressure cone angle a. According to ...


5

I am thinking that one could use several car batteries connected in series as the power source and a cable from these batteries would be connected to a high voltage transformer which would provide the high voltage for the Jacob's Ladder. Since we're talking about a balloon, you need energy to heat the air, and that energy will be stored in something like a ...


5

The elevator control system stores various bits of information in a logical fashion. The system will be optimised to maximise the utility of the lift. This generally means moving the maximum number of people to their desired destinations in the minimum time. The logic is smart. If someone on the tenth floor presses the ▾ button the elevator will run ...


5

jpa made a good answer on why the weights wouldn't flex upwards. I'll add another point. Newton's third law says that for every action, there is an equal and opposite reaction. For the box to be slowed by this mechanism, it must exert a force on something else, in the same way gravity pulls up on earth and aerodynamic drag moves the air. However, this ...


4

Modern digital projector use a technique called DLP(digital light processing). They use an array of micromirorrs in order to point the white light source(often a bulb) that goes through a filter to become colored (red, green or blue). There is a mirror for each pixel and it direct light to the projecting lens or to an absorber depending on if the pixel ...


4

Imagine you were driving a car along the path shown in a cross section view of the radius - you need to make a 90 degree bend, and you need to stay inside the cones that denote the tolerance band. In the first image, you find yourself about to hit the cones, so steer sharply left, then almost hit the other cones, so steer right, left, right etc. In the ...


4

Budweiser made some design modification to regain its marketing and branding endeavours which had seen huge decline in sales threatening Budweiser's status as America's Best selling beer. The new design emphasized the iconic bowtie and updated its appearance giving it a eye-catching look, providing good holding experience which was easy to grip. After can ...


4

The bicycle disk as shown is inherently prone to shimmying and spiraling into an increasing flutter. I have an Ebike with a very similar disk brake and I have learned my lesson to be cautious with it. As for controlled caliper force, one could use a scissor mechanism with a hook on the bottom which could be loaded by the desired weights as per the schematic ...


4

in a subsonic air propeller blade, there are two sources of noise: first, the "hiss" of air moving past the blades and then blade passage noise which is a sound wave that sweeps around with the blade as it revolves, producing a sound pulse with each blade passage. It has a characteristic frequency of (prop revolutions per second) x (number of ...


4

You are unfortunately most likely correct, and your description even grazed right by the official terminology for such things: hostile design/architecture. As other answers have mentioned, such a design has some benefits. However, given that hostile architecture is a formal policy in many cities, I'd wager these benefits are more of a post-hoc ...


3

An option you may consider is called a rotegrity sphere. The numbers show the spacing for a unit radius sphere. For a one-half meter radius, divide the numbers by two and convert to millimeters. My first exposure was from TaffGoch web site which allowed me to build two different models of two sizes, one with 3D printed members, the other with laser cut ...


3

Characteristics of a US Bill Ultraviolet (UV) Detection Using of vertical florescent stripe that is undetectable to the naked eye, but glows brightly when exposed under UV light. Ultraviolet is the single most common method of counterfeit bill detection used in money counting machines due to its simplicity, affordability and relative effectiveness Magnetic (...


3

These drives are called slot loading optical drives. The mechanical arm grabs the disc and draws into the drive. Below is an image that shows the mechanical grab arm. Take a look at Clear Slot Loading Drive Mod Below are some references that might be helpful Slim Slot-In DVD Drive Mechanism - How does it work Slot loading optical disc drive


3

You are looking for a “vertical axis wind turbine”. See below for some design examples:


3

Requirement and Specification are standard English words. They don't mean anything different from the dictionary definitions. A requirement is "something you need, or something you must have." A specification is "how to do something" or "how to make something."


3

The basic thing you are looking at is a dynamometer - a generator mounted on trunnions to measure the reactive force. So, look at those then use a smaller motor as a generator - the ones I used were capable of controlling 100 to 150 kW - a bit large for what you describe.


3

Sometimes concerns such as discouraging use of the bench for purposes such as loitering or being taken over by homeless guide the design. Also it is hard to leave a possible hazardous package on the bench covered by a rag. And if they are left somewhere on the ground it will catch the eye. This is an efficient way of temporary comfort for a passenger till ...


3

The design that you illustrated is pretty much correct. See below: In order for the end to move along a circular path, you want a four-bar-linkage with equal length arms. Note how the length of the medium grey linkages (60mm) is equal to the radius of the red circle (50mm), plus some clearance (10mm). Note how the distance from the centre of the red circle ...


3

Regarding the first question: why 1 ship is more efficient that 100 smaller ones. if you did some research I'm sure you'd find that one large ship probably uses about the same steel than a 10 smaller ones capable of carrying the same load. See evolution of container ships. A ship 200x20x10 meters could transport about one tenth of a ULCS (which is 400x59x16)....


3

Gas is odorized ( mercaptans ) which can be detected at a ppb level. The great majority of people notice the smell and take some corrective action. On the otherhand ,whenever you make something fool proof , a bigger fool comes along ; so there are occasional fires caused by gas leaks. Driving a car is a higher risk that having gas in a home or apartment ...


2

A company called Metalcraft Engineering Company Ltd made them out of 5mm steel plate for a another company that sell nuts and bolts. made by https://www.facebook.com/metalcraftengineering/photos/a.454442584764550/1263076980567769/ For these guys https://www.facebook.com/theconnectgroupnz/photos/2743380862386863


2

A Stirling engine is a way to remove heat from a heat source. So theoretically you could attach a Stirling engine to a radiator-like device and extract the heat using the engine. We could then use the output of the engine to do work. The most likely output would be an electric generator. Trying to use the Stirling engine to add power directly to the ...


2

There are a range of options for such a connection. I would put loctite for a plain grub screw at the bottom of the list. Depending on the safety aspects of the joint breaking loose, it might be very important for it not to slip. Your other options (in rough order of reliability): Grub screw to a flat-spotted shaft Grub screw into a drilled and tapped ...


2

Figure 1. Source: Wikipedia's Ball-bearing. The distance rolled on the inner ring is the same as the distance rolled on the outer ring. Due to the difference in circumference the ball will pass the same point on the inner ring about twice as often as it passes the same point on the outer ring (for these dimensions).


2

This colander was definitely not CNC machined, it was injection molded. Without being able to inspect the part closely, I will guess that the shutoffs (the open spaces between the plastic ribs) were formed by a retractable feature in the mold which presses against the mold core during the injection process, and then is pulled away from the core when the mold ...


2

Papermaking uses rollers called Spreaders to spread the sheet out in the cross-direction (perpendicular to sheet movement). These are bowed rollers that use friction against the sheet to spread, and I suppose you could use it to compress a sheet. For such a small scale you would need to build it yourself. I feel like the design you show will only emboss ...


2

Typically in my experience, your 3 orthogonal edges of the rectangular blank are your first 3 datums. Your dowel hole would be the first machined feature and since it locates the rest of the features, this would be your 4th datum. Your subsequent features would reference that 4th datum, as well as any of the original 3 to tolerance the features.


2

Without a sketch your setup is difficult to visualise. A typical industrial solution would be to use an inductive proximity switch. These are non-contact, fast switching, water-proof, etc. Figure 1. A selection of inductive proximity switches. You seem to suggest that the switch and circuit will rotate. This means that you need to consider those forces ...


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